diff options
Diffstat (limited to 'lib/charsets.c')
| -rw-r--r-- | lib/charsets.c | 526 |
1 files changed, 526 insertions, 0 deletions
diff --git a/lib/charsets.c b/lib/charsets.c new file mode 100644 index 0000000..b893902 --- /dev/null +++ b/lib/charsets.c @@ -0,0 +1,526 @@ +/* + Text conversion from one charset to another. + + Copyright (C) 2001-2022 + Free Software Foundation, Inc. + + Written by: + Walery Studennikov <despair@sama.ru> + + This file is part of the Midnight Commander. + + The Midnight Commander is free software: you can redistribute it + and/or modify it under the terms of the GNU General Public License as + published by the Free Software Foundation, either version 3 of the License, + or (at your option) any later version. + + The Midnight Commander is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +/** \file charsets.c + * \brief Source: Text conversion from one charset to another + */ + +#include <config.h> + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include "lib/global.h" +#include "lib/strutil.h" /* utf-8 functions */ +#include "lib/fileloc.h" +#include "lib/util.h" /* whitespace() */ + +#include "lib/charsets.h" + +/*** global variables ****************************************************************************/ + +GPtrArray *codepages = NULL; + +unsigned char conv_displ[256]; +unsigned char conv_input[256]; + +const char *cp_display = NULL; +const char *cp_source = NULL; + +/*** file scope macro definitions ****************************************************************/ + +#define UNKNCHAR '\001' + +#define OTHER_8BIT "Other_8_bit" + +/*** file scope type declarations ****************************************************************/ + +/*** file scope variables ************************************************************************/ + +/*** file scope functions ************************************************************************/ +/* --------------------------------------------------------------------------------------------- */ + +static codepage_desc * +new_codepage_desc (const char *id, const char *name) +{ + codepage_desc *desc; + + desc = g_new (codepage_desc, 1); + desc->id = g_strdup (id); + desc->name = g_strdup (name); + + return desc; +} + +/* --------------------------------------------------------------------------------------------- */ + +static void +free_codepage_desc (gpointer data, gpointer user_data) +{ + codepage_desc *desc = (codepage_desc *) data; + (void) user_data; + + g_free (desc->id); + g_free (desc->name); + g_free (desc); +} + +/* --------------------------------------------------------------------------------------------- */ +/* returns display codepage */ + +static void +load_codepages_list_from_file (GPtrArray ** list, const char *fname) +{ + FILE *f; + char buf[BUF_MEDIUM]; + char *default_codepage = NULL; + + f = fopen (fname, "r"); + if (f == NULL) + return; + + while (fgets (buf, sizeof buf, f) != NULL) + { + /* split string into id and cpname */ + char *p = buf; + size_t buflen; + + if (*p == '\n' || *p == '\0' || *p == '#') + continue; + + buflen = strlen (buf); + + if (buflen != 0 && buf[buflen - 1] == '\n') + buf[buflen - 1] = '\0'; + while (*p != '\0' && !whitespace (*p)) + ++p; + if (*p == '\0') + goto fail; + + *p++ = '\0'; + g_strstrip (p); + if (*p == '\0') + goto fail; + + if (strcmp (buf, "default") == 0) + default_codepage = g_strdup (p); + else + { + const char *id = buf; + + if (*list == NULL) + { + *list = g_ptr_array_sized_new (16); + g_ptr_array_add (*list, new_codepage_desc (id, p)); + } + else + { + unsigned int i; + + /* whether id is already present in list */ + /* if yes, overwrite description */ + for (i = 0; i < (*list)->len; i++) + { + codepage_desc *desc; + + desc = (codepage_desc *) g_ptr_array_index (*list, i); + + if (strcmp (id, desc->id) == 0) + { + /* found */ + g_free (desc->name); + desc->name = g_strdup (p); + break; + } + } + + /* not found */ + if (i == (*list)->len) + g_ptr_array_add (*list, new_codepage_desc (id, p)); + } + } + } + + if (default_codepage != NULL) + { + mc_global.display_codepage = get_codepage_index (default_codepage); + g_free (default_codepage); + } + + fail: + fclose (f); +} + +/* --------------------------------------------------------------------------------------------- */ + +static char +translate_character (GIConv cd, char c) +{ + gchar *tmp_buff = NULL; + gsize bytes_read, bytes_written = 0; + const char *ibuf = &c; + char ch = UNKNCHAR; + int ibuflen = 1; + + tmp_buff = g_convert_with_iconv (ibuf, ibuflen, cd, &bytes_read, &bytes_written, NULL); + if (tmp_buff != NULL) + ch = tmp_buff[0]; + g_free (tmp_buff); + return ch; +} + +/* --------------------------------------------------------------------------------------------- */ +/*** public functions ****************************************************************************/ +/* --------------------------------------------------------------------------------------------- */ + +void +load_codepages_list (void) +{ + char *fname; + + /* 1: try load /usr/share/mc/mc.charsets */ + fname = g_build_filename (mc_global.share_data_dir, CHARSETS_LIST, (char *) NULL); + load_codepages_list_from_file (&codepages, fname); + g_free (fname); + + /* 2: try load /etc/mc/mc.charsets */ + fname = g_build_filename (mc_global.sysconfig_dir, CHARSETS_LIST, (char *) NULL); + load_codepages_list_from_file (&codepages, fname); + g_free (fname); + + if (codepages == NULL) + { + /* files are not found, add defaullt codepage */ + fprintf (stderr, "%s\n", _("Warning: cannot load codepages list")); + + codepages = g_ptr_array_new (); + g_ptr_array_add (codepages, new_codepage_desc (DEFAULT_CHARSET, _("7-bit ASCII"))); + } +} + +/* --------------------------------------------------------------------------------------------- */ + +void +free_codepages_list (void) +{ + g_ptr_array_foreach (codepages, free_codepage_desc, NULL); + g_ptr_array_free (codepages, TRUE); + /* NULL-ize pointer to make unit tests happy */ + codepages = NULL; +} + +/* --------------------------------------------------------------------------------------------- */ + +const char * +get_codepage_id (const int n) +{ + return (n < 0) ? OTHER_8BIT : ((codepage_desc *) g_ptr_array_index (codepages, n))->id; +} + +/* --------------------------------------------------------------------------------------------- */ + +int +get_codepage_index (const char *id) +{ + size_t i; + + if (codepages == NULL) + return -1; + if (strcmp (id, OTHER_8BIT) == 0) + return -1; + for (i = 0; i < codepages->len; i++) + if (strcmp (id, ((codepage_desc *) g_ptr_array_index (codepages, i))->id) == 0) + return i; + return -1; +} + +/* --------------------------------------------------------------------------------------------- */ +/** Check if specified encoding can be used in mc. + * @param encoding name of encoding + * @return TRUE if encoding is supported by mc, FALSE otherwise + */ + +gboolean +is_supported_encoding (const char *encoding) +{ + gboolean result = FALSE; + guint t; + + for (t = 0; t < codepages->len; t++) + { + const char *id; + + id = ((codepage_desc *) g_ptr_array_index (codepages, t))->id; + result |= (g_ascii_strncasecmp (encoding, id, strlen (id)) == 0); + } + + return result; +} + +/* --------------------------------------------------------------------------------------------- */ + +char * +init_translation_table (int cpsource, int cpdisplay) +{ + int i; + GIConv cd; + + /* Fill inpit <-> display tables */ + + if (cpsource < 0 || cpdisplay < 0 || cpsource == cpdisplay) + { + for (i = 0; i <= 255; ++i) + { + conv_displ[i] = i; + conv_input[i] = i; + } + cp_source = cp_display; + return NULL; + } + + for (i = 0; i <= 127; ++i) + { + conv_displ[i] = i; + conv_input[i] = i; + } + cp_source = ((codepage_desc *) g_ptr_array_index (codepages, cpsource))->id; + cp_display = ((codepage_desc *) g_ptr_array_index (codepages, cpdisplay))->id; + + /* display <- inpit table */ + + cd = g_iconv_open (cp_display, cp_source); + if (cd == INVALID_CONV) + return g_strdup_printf (_("Cannot translate from %s to %s"), cp_source, cp_display); + + for (i = 128; i <= 255; ++i) + conv_displ[i] = translate_character (cd, i); + + g_iconv_close (cd); + + /* inpit <- display table */ + + cd = g_iconv_open (cp_source, cp_display); + if (cd == INVALID_CONV) + return g_strdup_printf (_("Cannot translate from %s to %s"), cp_display, cp_source); + + for (i = 128; i <= 255; ++i) + { + unsigned char ch; + ch = translate_character (cd, i); + conv_input[i] = (ch == UNKNCHAR) ? i : ch; + } + + g_iconv_close (cd); + + return NULL; +} + +/* --------------------------------------------------------------------------------------------- */ + +void +convert_to_display (char *str) +{ + if (str != NULL) + for (; *str != '\0'; str++) + *str = conv_displ[(unsigned char) *str]; +} + +/* --------------------------------------------------------------------------------------------- */ + +GString * +str_nconvert_to_display (const char *str, int len) +{ + GString *buff; + GIConv conv; + + if (str == NULL) + return g_string_new (""); + + if (cp_display == cp_source) + return g_string_new (str); + + conv = str_crt_conv_from (cp_source); + + buff = g_string_new (""); + str_nconvert (conv, str, len, buff); + str_close_conv (conv); + return buff; +} + +/* --------------------------------------------------------------------------------------------- */ + +void +convert_from_input (char *str) +{ + if (str != NULL) + for (; *str != '\0'; str++) + *str = conv_input[(unsigned char) *str]; +} + +/* --------------------------------------------------------------------------------------------- */ + +GString * +str_nconvert_to_input (const char *str, int len) +{ + GString *buff; + GIConv conv; + + if (str == NULL) + return g_string_new (""); + + if (cp_display == cp_source) + return g_string_new (str); + + conv = str_crt_conv_to (cp_source); + + buff = g_string_new (""); + str_nconvert (conv, str, len, buff); + str_close_conv (conv); + return buff; +} + +/* --------------------------------------------------------------------------------------------- */ + +unsigned char +convert_from_utf_to_current (const char *str) +{ + unsigned char buf_ch[UTF8_CHAR_LEN + 1]; + unsigned char ch = '.'; + GIConv conv; + const char *cp_to; + + if (str == NULL) + return '.'; + + cp_to = get_codepage_id (mc_global.source_codepage); + conv = str_crt_conv_to (cp_to); + + if (conv != INVALID_CONV) + { + switch (str_translate_char (conv, str, -1, (char *) buf_ch, sizeof (buf_ch))) + { + case ESTR_SUCCESS: + ch = buf_ch[0]; + break; + case ESTR_PROBLEM: + case ESTR_FAILURE: + ch = '.'; + break; + default: + break; + } + str_close_conv (conv); + } + + return ch; +} + +/* --------------------------------------------------------------------------------------------- */ + +unsigned char +convert_from_utf_to_current_c (int input_char, GIConv conv) +{ + unsigned char str[UTF8_CHAR_LEN + 1]; + unsigned char buf_ch[UTF8_CHAR_LEN + 1]; + unsigned char ch = '.'; + int res; + + res = g_unichar_to_utf8 (input_char, (char *) str); + if (res == 0) + return ch; + + str[res] = '\0'; + + switch (str_translate_char (conv, (char *) str, -1, (char *) buf_ch, sizeof (buf_ch))) + { + case ESTR_SUCCESS: + ch = buf_ch[0]; + break; + case ESTR_PROBLEM: + case ESTR_FAILURE: + ch = '.'; + break; + default: + break; + } + + return ch; +} + +/* --------------------------------------------------------------------------------------------- */ + +int +convert_from_8bit_to_utf_c (char input_char, GIConv conv) +{ + unsigned char str[2]; + unsigned char buf_ch[UTF8_CHAR_LEN + 1]; + int ch; + + str[0] = (unsigned char) input_char; + str[1] = '\0'; + + switch (str_translate_char (conv, (char *) str, -1, (char *) buf_ch, sizeof (buf_ch))) + { + case ESTR_SUCCESS: + { + int res; + + res = g_utf8_get_char_validated ((char *) buf_ch, -1); + ch = res >= 0 ? res : buf_ch[0]; + break; + } + case ESTR_PROBLEM: + case ESTR_FAILURE: + default: + ch = '.'; + break; + } + + return ch; +} + +/* --------------------------------------------------------------------------------------------- */ + +int +convert_from_8bit_to_utf_c2 (char input_char) +{ + int ch = '.'; + GIConv conv; + const char *cp_from; + + cp_from = get_codepage_id (mc_global.source_codepage); + + conv = str_crt_conv_to (cp_from); + if (conv != INVALID_CONV) + { + ch = convert_from_8bit_to_utf_c (input_char, conv); + str_close_conv (conv); + } + + return ch; +} + +/* --------------------------------------------------------------------------------------------- */ |